Merge pull request #81 from FlowFuse/271-proxy-support

Proxy support

Author: Steve-Mcl

.eslintrc

@@ -9,11 +9,13 @@
     "extends": [
         "standard"
     ],
+    "plugins": [ "eslint-plugin-html", "no-only-tests" ],
     "parserOptions": {
         "ecmaVersion": 12
     },
     "rules": {
         "indent": ["error", 4],
-        "object-shorthand": ["error"]
+        "object-shorthand": ["error"],
+        "no-only-tests/no-only-tests": "error"
     }
 }

lib/utils.js

@@ -0,0 +1,75 @@
+const proxyFromEnv = require('proxy-from-env')
+
+module.exports = {
+    getWSProxyAgent,
+    getHTTPProxyAgent
+}
+
+/**
+ * Get a specific proxy agent for a WebSocket connection. This should be applied to the `wsOptions.agent` property
+ *
+ * NOTE: This utility function is specifically designed for the MQTT instances where the proxy is set based on the http based EndPoint
+ *       that the instance will use to make a connection. As such, the proxy URL is determined based on the `wsEndPoint` provided in
+ *       conjunction with env vars `http_proxy`, `https_proxy` and `no_proxy`.
+ *
+ * More Info:
+ *   `wsOptions.agent` is expected to be an HTTP or HTTPS agent based on the request protocol
+ *   http/ws requests use env var `http_proxy` and the HttpProxyAgent
+ *   https/wss requests use env var `https_proxy` and the HttpsProxyAgent
+ *   REF: https://github.com/TooTallNate/proxy-agents/tree/main/packages/proxy-agent#maps-proxy-protocols-to-httpagent-implementations
+ *
+ * @param {String} url - WebSocket url
+ * @param {import('http').AgentOptions} proxyOptions - proxy options
+ * @returns {import('https-proxy-agent').HttpsProxyAgent | import('http-proxy-agent').HttpProxyAgent | null}
+ */
+function getWSProxyAgent (url, proxyOptions) {
+    if (!url) {
+        return null
+    }
+    const _url = new URL(url)
+    const isHTTPBased = _url.protocol === 'ws:' || _url.protocol === 'http:'
+    const isHTTPSBased = _url.protocol === 'wss:' || _url.protocol === 'https:'
+    if (!isHTTPBased && !isHTTPSBased) {
+        return null
+    }
+
+    // replace ^ws with http so that getProxyForUrl can return the correct http*_proxy for ws/wss
+    const proxyUrl = proxyFromEnv.getProxyForUrl(url.replace(/^ws/, 'http'))
+
+    if (proxyUrl && isHTTPSBased) {
+        const HttpsAgent = require('https-proxy-agent').HttpsProxyAgent
+        return new HttpsAgent(proxyUrl, proxyOptions)
+    }
+    if (proxyUrl && isHTTPBased) {
+        const HttpAgent = require('http-proxy-agent').HttpProxyAgent
+        return new HttpAgent(proxyUrl, proxyOptions)
+    }
+    return null
+}
+
+/**
+ * Get proxy agent for HTTP or HTTPS got instance. This should be applied to the `agent` property of the got instance options
+ *
+ * NOTE: This utility function is specifically designed for the GOT instances where the proxy is set based on the `httpEndPoint`
+ *       that the instance will use to make requests. As such, the proxy URL is determined based on the `httpEndPoint` provided
+ *       in conjunction with env vars `http_proxy`, `https_proxy` and `no_proxy`.
+ * @param {String} url - http or https URL
+ * @param {import('http').AgentOptions} proxyOptions - proxy options
+ * @returns {{http: import('http-proxy-agent').HttpProxyAgent | undefined, https: import('https-proxy-agent').HttpsProxyAgent | undefined}}
+ */
+function getHTTPProxyAgent (url, proxyOptions) {
+    const agent = {}
+    if (url) {
+        const _url = new URL(url)
+        const proxyUrl = proxyFromEnv.getProxyForUrl(url)
+        if (proxyUrl && _url.protocol === 'http:') {
+            const HttpAgent = require('http-proxy-agent').HttpProxyAgent
+            agent.http = new HttpAgent(proxyUrl, proxyOptions)
+        }
+        if (proxyUrl && _url.protocol === 'https:') {
+            const HttpsAgent = require('https-proxy-agent').HttpsProxyAgent
+            agent.https = new HttpsAgent(proxyUrl, proxyOptions)
+        }
+    }
+    return agent
+}

nodes/project-link.js

@@ -8,9 +8,10 @@ module.exports = function (RED) {
 
     // Imports
     const crypto = require('crypto')
-    const got = require('got')
+    const { default: GOT } = require('got')
     const MQTT = require('mqtt')
     const urlModule = require('url')
+    const utils = require('../lib/utils.js')
 
     // Constants
     const API_VERSION = 'v1'
@@ -631,6 +632,14 @@ module.exports = function (RED) {
                     const parsedURL = urlModule.parse(brokerURL)
                     const newURL = new URL(brokerURL)
                     parsedURL.hostname = newURL.hostname
+
+                    // wsOptions.agent is expected to be an HTTP or HTTPS agent based on the request protocol
+                    if (process.env.all_proxy || process.env.http_proxy || process.env.https_proxy) {
+                        options.wsOptions = {
+                            agent: utils.getWSProxyAgent(brokerURL)
+                        }
+                    }
+
                     client = MQTT.connect(parsedURL, options)
                     clients.push(client) // add to clients array for containment and auto cleanup of multiple clients
                     on('connect', onConnect)
@@ -1056,6 +1065,10 @@ module.exports = function (RED) {
     }
     RED.nodes.registerType('project link call', ProjectLinkCallNode)
 
+    const got = GOT.extend({
+        agent: utils.getHTTPProxyAgent(RED.settings.flowforge.forgeURL, { timeout: 4000 })
+    })
+
     // Endpoint for querying list of projects in node UI
     RED.httpAdmin.get('/nr-project-link/projects', RED.auth.needsPermission('flows.write'), async function (_req, res) {
         const url = `${RED.settings.flowforge.forgeURL}/api/${API_VERSION}/teams/${RED.settings.flowforge.teamID}/projects`